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Hollmann, F. (author), Arends, I.W.C.E. (author)
Biocatalysis is propagating into practically every area of organic chemistry, amongst them radical polymerizations. A review of the recent developments of this dynamic and quickly evolving area of research is presented together with a critical evaluation of its potential to yield novel polymers and/or environmentally more benign synthetic...
journal article 2012
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Chen, B.S. (author), Resch, V. (author), Otten, L.G. (author), Hanefeld, U. (author)
The enantioselective Michael addition using water as both nucleophile and solvent has to date proved beyond the ability of synthetic chemists. Herein, the direct, enantioselective Michael addition of water in water to prepare important ?-hydroxy carbonyl compounds using whole cells of Rhodococcus strains is described. Good yields and excellent...
journal article 2014
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De Torres, M. (author), Dimroth, J. (author), Arends, I.W.C.E. (author), Keilitz, J. (author), Hollmann, F. (author)
Rh(III)-TsDPEN, an immobilized analog of the well-known [Cp*Rh(bpy)(H2O)]2+ was evaluated as a heterogeneous, recyclable regeneration catalyst for reduced oxidoreductase cofactors [NAD(P)H]. Repeated use of this catalyst was established and the catalytic properties were initially investigated. Apparently, Rh(III)-TsDPEN is prone to severe...
journal article 2012
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Straathof, A.J.J. (author)
journal article 2013
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Chen, B.S. (author), Otten, L.G. (author), Resch, V. (author), Muyzer, G. (author), Hanefeld, U. (author)
Rhodococcus rhodochrous ATCC 17895 possesses an array of mono- and dioxygenases, as well as hydratases, which makes it an interesting organism for biocatalysis. R. rhodochrous is a Gram-positive aerobic bacterium with a rod-like morphology. Here we describe the features of this organism, together with the complete genome sequence and annotation....
journal article 2013
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Hiseni, A. (author), Arends, I.W.C.E. (author), Otten, L.G. (author)
Two carotenoid 1,2-hydratase (CrtC) genes from the photosynthetic bacteria Rubrivivax gelatinosus and Thiocapsa roseopersicina were cloned and expressed in Escherichia coli in an active form and purified by affinity chromatography. The biochemical properties of the recombinant enzymes and their substrate specificities were studied. The purified...
journal article 2011
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Hiseni, A. (author), Otten, L.G. (author), Arends, I.W.C.E. (author)
Carotenoid 1,2-hydratases (CrtC) catalyze the selective addition of water to an isolated carbon–carbon double bond. Although their involvement in the carotenoid biosynthetic pathway is well understood, little is known about the mechanism by which these hydratases transform carotenoids such as lycopene into the corresponding hydroxyl compounds....
journal article 2015
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Burek, Bastien O. (author), Dawood, A.W.H. (author), Hollmann, F. (author), Liese, Andreas (author), Holtmann, Dirk (author)
Enzyme catalysis, made tremendous progress over the last years in identification of new enzymes and new enzymatic reactivity’s as well as optimization of existing enzymes. However, the performance of the resulting processes is often still limited, e.g., in regard of productivity, realized product concentrations and the stability of the enzymes....
journal article 2022
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Silva de Miranda, Amanda (author), Milagre, C.D.D.F. (author), Hollmann, F. (author)
Alcohol dehydrogenases (ADHs) have become important catalysts for stereoselective oxidation and reduction reactions of alcohols, aldehydes and ketones. The aim of this contribution is to provide the reader with a timely update on the state-of-the-art of ADH-catalysis. Mechanistic basics are presented together with practical information about the...
journal article 2022
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Hagedoorn, P.L. (author)
Isothermal titration calorimetry (ITC) is a popular chemical analysis technique that can be used to measure macromolecular interactions and chemical and physical processes. ITC involves the measurement of heat flow to and from a measurement cell after each injection during a titration experiment. ITC has been useful to measure the thermodynamics...
journal article 2022
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Puchľová, Eva (author), Hilberath, T. (author), Vranková, Kvetoslava (author), Hollmann, F. (author)
Non-enantioselective alcohol dehydrogenases (ADHs) are rarely found in the biocatalysis portfolio. Generally, highly enantioselective ADHs are sought for. Using such ADHs for the oxidation of racemic alcohols generally results in a kinetic resolution of the starting material, which is unfavourable if the ketone represents the product of interest...
journal article 2022
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França, Alexandre S. (author), Brêda, Gabriela C. (author), De Oliveira, Kleber T. (author), Almeida, Rodrigo V. (author), Hollmann, F. (author), de Souza, Rodrigo O.M.A. (author)
A visible-light-driven photocatalytic decarboxylation of palmitic acid and related fatty acids is described in this study. Remarkable decarboxylation rates have been observed with full conversion in less than 20 min. In this study, we have<br/>demonstrated that sunlight irradiation, even on cloudy days, can deliver similar results to traditional...
journal article 2023
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Zhang, W. (author), Li, Huanhuan (author), Younes, S.H.H. (author), Gómez De Santos, Patricia (author), Tieves, F. (author), Grogan, Gideon (author), Pabst, Martin (author), Alcalde, Miguel (author), Whitwood, Adrian C. (author), Hollmann, F. (author)
Aromatic hydroxylation reactions catalyzed by heme-thiolate enzymes proceed via an epoxide intermediate. These aromatic epoxides could be valuable building blocks for organic synthesis giving access to a range of chiral trans-disubstituted cyclohexadiene synthons. Here, we show that naphthalene epoxides generated by fungal peroxygenases can...
journal article 2021
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Chatzipanagiotou, Konstantina Roxani (author), Soekhoe, Virangni (author), Jourdin, L. (author), Buisman, Cees J.N. (author), Bitter, J. Harry (author), Strik, David P.B.T.B. (author)
Electrocatalytic metals and microorganisms can be combined for CO2 conversion in microbial electrosynthesis (MES). However, a systematic investigation on the nature of interactions between metals and MES is still lacking. To investigate this nature, we integrated a copper electrocatalyst, converting CO2 to formate, with microorganisms,...
journal article 2021
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Duong, Hong T. (author), Wu, Y. (author), Sutor, Alexander (author), Burek, Bastien O. (author), Hollmann, F. (author), Bloh, Jonathan Z. (author)
Light-driven biocatalytic processes are notoriously hampered by poor penetration of light into the turbid reaction media. In this study, wirelessly powered light-emitting diodes are found to represent an efficient and scalable approach for process intensification of the photobiosynthetic production of diesel alkanes from renewable fatty acids...
journal article 2021
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Ribeaucourt, David (author), Höfler, G.T. (author), Yemloul, Mehdi (author), Bissaro, Bastien (author), Lambert, Fanny (author), Berrin, Jean Guy (author), Lafond, Mickael (author), Paul, C.E. (author)
Biocatalytic pathways for the synthesis of (-)-menthol, the most sold flavor worldwide, are highly sought-after. To access the key intermediate (R)-citronellal used in current major industrial production routes, we established a one-pot bienzymatic cascade from inexpensive geraniol, overcoming the problematic biocatalytic reduction of the...
journal article 2022
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Song, Ji Won (author), Baeg, Yoonjin (author), Jeong, Ha Yeon (author), Lee, Jinwon (author), Oh, Deok Kun (author), Hollmann, F. (author), Park, Jin Byung (author)
Bacterial outer membrane vesicles (OMVs) are small unilamellar proteoliposomes, involved in various functions including cell-to-cell signalling and protein excretion. We have engineered the OMVs of Escherichia coli to nano-scaled bioreactors for the biotransformation of fatty acids by targeting a fatty acid double bond hydratase of...
journal article 2021
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Nieto, Susana (author), Bernal, Juana M. (author), Villa Aroca, R. (author), Garcia-Verdugo, Eduardo (author), Donaire, Antonio (author), Lozano, Pedro (author)
A sustainable scaling-up process for the biocatalytic production of new bioactive provitamin-B<sub>5</sub> monoacyl esters has been demonstrated. A solvent-free reaction protocol, based on the formation of eutectic mixtures between neat substrates, renders highly efficient direct esterification of free fatty acids (i.e., from C<sub>6</sub> to...
journal article 2023
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Bormann, Sebastian (author), van Schie, M.M.C.H. (author), Pedroso de Almeida, T. (author), Zhang, W. (author), Stöckl, Markus (author), Ulber, Roland (author), Hollmann, F. (author), Holtmann, Dirk (author)
Various enzymes utilize hydrogen peroxide as an oxidant. Such “peroxizymes” are potentially very attractive catalysts for a broad range of oxidation reactions. Most peroxizymes, however, are inactivated by an excess of H<sub>2</sub>O<sub>2</sub>. The electrochemical reduction of oxygen can be used as an in situ generation method for hydrogen...
journal article 2019
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Yin, Xinjian (author), Gong, Wenzhong (author), Zeng, Yujing (author), Qiu, Hulin (author), Liu, Lan (author), Hollmann, F. (author), Chen, Bishuang (author)
The biocatalytic oxidative deamination of β-amino alcohols holds significant practical potential in kinetic resolution and/or deracemization process to access (R)-β-amino alcohols. This study exemplifies a notable instance of acquisition and utilization of this valuable oxidative deamination activity. Initially, the mutation N261M (M0) was...
journal article 2024
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